Extended Strong's Greek Lexicon (Abbott-Smith based)
tetrarch
Usage: τετραάρχης (Rec. τετράρχης, see supr.), -ου, ὁ (τετρα- in corp. = τέτορα, Doric for τέσσαρα, + ἄρχω), a tetrarch, i.e. __(a) prop., the governor of a fourth part of a region (Strab.); __(b) any petty ruler (Plut.); in NT, of Herod Antipas: Mat.14:1, Luk.3:19 9:7, Act.13:1.† (AS)